Weight distribution and postural sway in healthy adults

Abstract

An investigation of postural sway and bodyweight distribution in standing was carried out using the Nottingham Balance Platform (NBP). The aims were to provide normative data for subsequent studies on stroke patients and to show the effect of age and sex on these variables. Male and female volunteers were recruited from hospital workers, hospital visitors and members of a local community centre. Each subject was assessed using the N BP, a limb load monitor based on load cells and a microcomputer. Weight distribution was expressed as the balance coefficient, which is the mean proportion of body weight on the left leg calculated over 30 seconds. Postural sway was calculated from the deviation from that mean and expressed as the sway coefficient. The 403 volunteers included 269 women and 134 men, age range 18-87 years (mean 50). There was a significant difference between the sexes for both postural sway (p < 0.05) and weight distribution (p < 0.01) and significant correlations between age and postural sway (p < 0.001) and age and weight distribution (p < 0.001). The results provided baseline data allowing for age and sex differences for further studies with stroke patients

Postural Asymmetries in Response to Holding Evenly and Unevenly Distributed Loads During Self-Selected Stance

“…Alternatively, it has been suggested that, similar to gait, postural asymmetries may be functional. To date, only a handful of studies have examined postural asymmetry in healthy young adults (Anker et al, 2008;Aruin, 2006;Blaszczyk, Prince, Raiche, & Hebert, 2000;Genthon & Rougier, 2005;Hesse, Schauer, & Jahnke, 1996;Sackley & Lincoln, 1991), and these studies typically only examine asymmetry in weight distribution. Little work has examined asymmetries that are present in the center of pressure (CoP) characteristics between the right and left limbs (Anker et al; Genthon & Rougier).…”

“…This observed asymmetry in weight distribution appears to increase with age (Blaszcyk et al; Sackley & Lincoln, 1991). However, it is still not clear if the limbs are used differentially to control balance in a self-selected posture during standing.…”

Ordinal and timed balance measurements: reliability and validity in patients with stroke

“…Balance and related behaviours have been described using a number of different measures including ordinal scales,2-4 timed efforts,5,6 centre of gravity location and/or sway,7,8 distance of reach,9 response to perturbation, 10-12 balance beam walkingl3 and weight-bearing symmetry. 8, [14][15][16] For measures applied to patients with stroke, Wade et al. suggested that there are three essential and four desirable characteristics.…”

Weight distribution influences the time required to lift the leg even under normal standing condition

“…However, a careful review of the previous studies shows that spontaneous bipedal standing is not strictly a symmetrical posture, even for healthy young people [8,10]; thus, several questions are left unresolved. First, in daily life, standing posture is not controlled but is spontaneously regulated.…”